1. Field of the Invention
The present invention relates to an automatic control apparatus for an engine, and in particularly, to an automatic control apparatus for an engine which is capable of performing idling stop to enable the engine to be automatically stopped and idling start to enable the engine to be automatically restarted according to an operation position of a mechanical shift lever which is a shift lever operated by a driver to switch shift stages of a transmission between a plurality of shift ranges.
2. Description of Related Art
An automatic control apparatus for an engine is known, which detects an operation position of a mechanical shift lever that is operated by the driver to switch shift stages of a transmission between a plurality of shift ranges, and performs idling stop to enable the engine to be automatically stopped and idling start to enable the engine to be automatically restarted according the operation position (for example, refer to Japanese Patent Application Publication No. JP 10-77937 (JP 10-77937A)).
With the automatic control apparatus for an engine as described in the above JP 10-77937A, after the operation position of the mechanical shift lever is switched to the Reverse range while the engine is stopped by the idling stop, in the case where the operation position is maintained at the Reverse range for a certain predetermined time, the engine is restarted by the idling start. In this configuration, if the operation position is not maintained at the Reverse range for the predetermined time, the engine is continuously stopped by the idling stop; on the other hand, if the operation position is maintained at the Reverse range for the predetermined time, the stop state of the engine achieved by the idling stop is released by the idling start, and the engine is restarted.
Therefore, according to the above automatic control apparatus for an engine, it is possible not only to suppress the fuel consumption of the engine by means of the idling stop, but also to ensure the vehicle to be started smoothly by means of the idling start. In addition, when the operation position of the mechanical shift lever only passes by the Reverse range while the engine is stopped by the idling stop, in the case where the driver switches the operation position of the mechanical shift lever for example from the Drive range to the Park range, it is possible to prevent the engine from being mistakenly restarted, and therefore, the fuel economy of the engine can be improved.
However, as mentioned above, the engine which has been stopped by the idling stop can be restarted by the idling start only after the operation position of the mechanical shift lever is maintained at the Reverse range for a constant certain time, so, for example, when the driver has the intention to immediately start the vehicle which is in the idling stop, when the operation speed of the mechanical shift lever varies for different drivers, and so on, sometimes, the driver would feel that the vehicle has poor start response.